According to The Hollywood Reporter, Elizabeth Henstridge (pictured above) and Iain De Caestecker are the latest performers to sign on for the “S.H.I.E.L.D.” pilot. Henstridge will portray Agent Gemma Simmons and De Caestecker will play Agent Leo Fitz. Both Simmons and Fitz are said to be technical geniuses who spend most of their time together bickering.

Prior to joining this project, Henstridge appeared in the TV series, “Hollyoaks” as well as the films Delicacy and The Thompsons. De Caestecker has extensive experience on British television, with stints on “Young James Herriot,” “The Fades,” “Lip Service,” “Coronation Street” and “The Secret of Crickley Hall.”

Whedon is co-writing the script for “S.H.I.E.L.D.” with his brother, Jed Wedon and Maurissa Tancharoen. The trio previously collaborated on “Dr. Horrible's Sing-Along Blog.” Whedon may also direct the pilot episode depending upon his schedule. But it has not yet been confirmed that he will.

If “S.H.I.E.L.D.” begins filming in January 2013 as rumored, that would place it squarely in contention for a fall 2013 pickup at ABC.

Who should be cast as Skye and Grant in the “S.H.I.E.L.D.” pilot? Share your picks in the comment section below!